© 2022
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WTC3243 TEMPERATURE CONTROLLER
ADJUST THE TEMPERATURE SETPOINT
VOLTAGE
The setpoint voltage can be adjusted either by using the
evaluation board’s onboard SET T trimpot or by connecting
a remote voltage source or potentiometer to the RSET or
HSET inputs. Only one of these setpoints can be used.
When controlling correctly, the SET T matches the ACT T at
the desired temperature.
The setpoint voltage can also be adjusted using the
evaluation board by connecting a remote voltage source
or potentiometer to the remote setpoint (RSET) or the high
voltage setpoint (HSET) inputs.
To adjust the SET T, with the voltmeter attached to the
SET T and COM wires, turn the SET T trimpot screw. Rotate
the trimpot clockwise to increase or counter-clockwise to
decrease the voltage. The SET T trimpot can be adjusted
from 0 V to 5 V. To get above 4.5 V, increase V
DD
to a
minimum of 5.5 V. To read the actual temperature and
setpoint temperature of the device, the power needs to be
connected.
NOTE: If you are not getting a setpoint reading, make sure
your VSET jumper is set correctly.
• The RSET input is subject to the Data Acquisition
(DAQ) Failsafe Protection circuit. If RSET drops below
0.3 V, the setpoint will be overridden and set to 1 V. See
the
Additional Technical Notes
section for changing
these defaults. RSET is limited to 0 to 6.5 V.
• The HSET remote setpoint input is not subject to the
DAQ Failsafe Protection circuit. It is limited to 0 to
(V
DD
– 2.5 V).
ENABLE AND DISABLE THE OUTPUT CURRENT
Toggle the ENABLE switch to ON. Output is enabled when
the green LED light is on. If there is no power to V
S
, the LED
will not light.
With the power connected, an external enable signal to the
remote enable (REN) on TB2 can be used.
0 V
= ENABLE
Floating or >3 V
= DISABLED
The onboard switch overrides the external signal.
